During the episode "Dawg Days" after Thurmond's mother calls the police because her deceased son's body was taken from his grave, her glasses alternate between being on her face and off her face between shots.
In the scene in the Strike Team's club house were Vic Mackey tells Officer Sofer that he "took care of it" Vic can be seen cleaning his gun. When Officer Sofer enters the room Vic is just about to begin to clean the barrel, but when the shot changes he is part way through and removes the brush.
When Julien is talking to Thurmond's mother, she is alternately wearing/not wearing glasses.
In the club scene Catherine Dent threatens to "call in the calvary". This is a common mistake amount Christian protestants who grew up hearing about calvary as being the location of the crucifixion. In American television, approximately three out of five actors mispronounce this word. The correct term is "cavalry", which means mounted soldiers (formerly horse soldiers and today, tank crews).
As Vic is running around the corner through to the alley, to where the car's horn is blaring, the legs of the camera crew running next to him are visible.
When Dutch and Claudette visit the construction site, it can see the cameramen following them backwards in a zoomed out shot that passes through the building under construction.